Yes it is possible. Guitar Pro includes a MIDI input that allows you to capture notes that way.
Please note the MIDI capture is not in real time though but one beat at a time.
You will need a MIDI device for that purpose. Either a plain MIDI instrument such as the Jamstik guitar, You Rock guitar, MIDI Keyboard...Or you can also use a MIDI controller as an interface between your guitar and your computer.
Activate this option from the Sound > MIDI Capture menu and select your peripheral from the Device entry.